fix(deps): update dependency next to v15.4.7 [security]

Author: renovate[bot]

website/package.json

@@ -13,7 +13,7 @@
   },
   "dependencies": {
     "@theguild/components": "^9.1.2",
-    "next": "15.2.4",
+    "next": "15.4.7",
     "next-sitemap": "4.2.3",
     "react": "^19.0.0",
     "react-dom": "^19.0.0"